<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #richedit{
            width: 200px;
            height: 200px;
            border: 1px solid red;
        }
    </style>
</head>
<body>
<div class="editable" id="richedit" contenteditable></div>
<script>
    /*
        任何元素指定 contenteditable 属性，然后该元素会立即被用户编辑。
     */
</script>
</body>
</html>